package org.example.state;

import org.apache.flink.api.common.eventtime.WatermarkStrategy;
import org.apache.flink.api.common.state.MapState;
import org.apache.flink.api.common.state.MapStateDescriptor;
import org.apache.flink.api.common.state.ReducingState;
import org.apache.flink.api.common.state.ReducingStateDescriptor;
import org.apache.flink.api.common.typeinfo.Types;
import org.apache.flink.configuration.Configuration;
import org.apache.flink.streaming.api.datastream.DataStreamSource;
import org.apache.flink.streaming.api.datastream.SingleOutputStreamOperator;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.api.functions.KeyedProcessFunction;
import org.apache.flink.util.Collector;
import org.example.data.WaterSensor;
import org.example.function.WaterSensorMapFunction;

import java.time.Duration;
import java.util.Optional;

/**
 * 计算每种传感器的水位和
 */
public class KeyReduceStateDemo {
    public static void main(String[] args) throws Exception {
        StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
        env.setParallelism(1);
        DataStreamSource<String> source = env.socketTextStream("localhost", 9999);
        SingleOutputStreamOperator<WaterSensor> sensorDS = source.map(new WaterSensorMapFunction());

        WatermarkStrategy<WaterSensor> waterSensorWatermarkStrategy = WatermarkStrategy
                //指定乱序的Watermark生成，延时。
                .<WaterSensor>forBoundedOutOfOrderness(Duration.ofSeconds(3))
                .withTimestampAssigner((WaterSensor waterSensor, long l) -> {
                    //返回的时间戳 毫秒
                    return waterSensor.getTs() * 1000;
                });

        SingleOutputStreamOperator<String> process = sensorDS.keyBy(WaterSensor::getId).process(new KeyedProcessFunction<String, WaterSensor, String>() {
            //可以定义多个状态
            ReducingState<Integer> vcReduceState;
            //ValueState<String> lastIdValue;

            @Override
            public void open(Configuration parameters) throws Exception {
                super.open(parameters);
                vcReduceState = getRuntimeContext().getReducingState(new ReducingStateDescriptor<>("vcReduceState", (v1, v2) -> v1 + v2, Types.INT));

            }

            //reduce 输入类型，输出类型，中间类型要一样
            @Override
            public void processElement(WaterSensor value, KeyedProcessFunction<String, WaterSensor, String>.Context ctx, Collector<String> out) throws Exception {
                vcReduceState.add(value.getVc());
                out.collect("传感器：" + ctx.getCurrentKey() + " 水位累加值：" + vcReduceState.get());
            }
        });
        process.printToErr("");
        env.execute("KeyReduceStateDemo");
    }
}
